Problem: Evaluate the following expression when $c = 5$ and $d = 9$. $10$ $c$ $ + 3$ $d$ $ - 5$
Explanation: Substitute $5$ for ${c}$ and $9$ for ${d}$ $ = 10{(5)} + 3{(9)} - 5 $ $ = 50 + 27 - 5 $ $ = 72$